The purpose of the pathology core facility is to provide a central facility for procuring and processing tissue and distributing it to the various investigators. One central facility for procurement and distribution will provide equitable and timely processing, assure consistent and reliable results, and will prevent duplication of technical effort or instrumentation among the various investigators. The processing will include frozen section and paraffin histology, image analysis, flow cytometry, electron microscopy, immunohistochemistry and cytogenetics. Molecular biology techniques, including amplification of DNA and RNA and in situ hybridization will be used in a cooperative venture between the research laboratories of Dr. Lebovitz and Dr. Lieberman. The results of testing by various investigators will be matched with all of the clinical and pathological information on patients and experimental animals and be analyzed by members of the Design and Analysis Core.